A 4-hydroxyphenylpyruvate dioxygenase inhibitor (hereinafter, referred to as a “HPPD inhibitor”) is known as a useful herbicide, but development in effects may be delayed depending on formulations or fields environment, and some of factors for the delay are still unclear.
Therefore, formulation techniques for immediately and stably developing a HPPD inhibitory effect, regardless of formulations or field conditions, are required.
In agricultural fields, inorganic phosphorus compounds are known to be used as fertilizers or physical-property modifiers for agricultural chemicals. For example, Patent Document 1 discloses a water-surface floatable granular agrichemical composition containing an agrichemical active ingredient, a specific alkanediol derivative, a condensed phosphoric acid or a salt thereof, a floating aid and a bulking filler, and it describes that the diffusivity of the water-surface floatable granular agrichemical composition is dependent on presence or absence of the salt of condensed phosphoric acid.
However, Patent Document 1 neither discloses nor suggests that the salt of condensed phosphoric acid is associated with development of a HPPD inhibitory effect, and further it neither discloses nor suggests that the salt of condensed phosphoric acid influences development of a HPPD inhibitory effect since it has no herbicidal activity with a usual dosage.